Forming means



' Feb. 20, 1934. J. moms 5 1,947,611

FORMING nuns J Filed April 29. 1932" 4Sheets-Sheet 2 A 7' TOENE K I J. MIOTKE 1 1,947,611

FORMING isms Feb. 20, 1934.

Filed April 29, 1952 4 Sheets-Sheet 3 fNVENTOE: fisepfi Niof/re. v W

rromvzsc Feb. 20, 1934. J. MIOTKE' I mum. unlms Filed. April 29,. 1932 4 Sheets-Sheet 4 N mmyroz. Jose-pl: Moi/ta. Q1

Patented Feb. 20, 1934 I a I UNITED STATES PATENT OFFICE I FORMING MEANS Joseph Miotke, Milwaukee, Wis.

Application April 29, 1932. Serial No. 608,221

' 11 Claims. (01. 113-44) This invention relates to forming sheet metal Similar characters of reference apply to like objects by progressive steps wherein varying dies features throughout the several figures. transform a closed tubular element employed as The disclosures are, in a sense, diagrammatic; the base stock. the ultimate details of tool equipmenthave been v The objects of the invention are: omitted to leave only the essential elements 80 The providing of means whereby a tubular which will answer the purpose here concerned.

- sheet metal object is peculiarly shaped so that The various mechanical appurtenances actually its physical properties and stability are prer quired. as W ll as t vari us p rams of served intact through the use of instrumentalithose progressive methods necessary to the ties which require a fluid medium in certain a d of the Dreduet Worked. are numerous. 65 steps of a progressive series of operations necesand subject to such mechanical preferences as sary in order to obtain a specifically designed will best suit the kind of work performed and article. the kind of product worked in order to get the The offering of means whereby a singular and respective results desired. The present discloregularly cylindrical tube is partially elongated, Sure eonfines itself t0 -p pou e 618- tapered and then arcuately bent to assume a rement. but it is here remarked that the d verse-curve aspect beyond its original cylindrical P duc Object y be Other forms requiring shape, 'or other forms approximating th first Y like treatment for shaping articles of the tubular recited design, wherein occur the necessity for a d hollow Sheet metal Variety in Order that the imparting curved and tapering aspects in aholcostly methods now in vogue will be eliminated, 75 low element having one of its two ends sealed as Well as Ofiering a Stronger, Smoother. a d a until the several necessary operations are commore regularly Contoured p od vin uc pleted. I curvatures as will readily fall within the class The means employed are disclosed in th of designs equivalent to the chosen specimen.

companying drawings, to which the following Referring to t d awings. Fig. 1 comp specification and appended claims refer. The forming-press elements pp y an ed to various figures are indexed as follows;- I oijier a divided and arcuately contoured angular Fig. l is a sectional side elevation of the Cavity C formed y a f d d e-b1061 land a initial forming step. movable die-block 2, the latter slidably mounted 30 Fig. 2 is a similar elevation of the second in a Suitable bed-block B wherein the y step. which function as guides that direct the said Fig. 3 is a section on line 3 3 of Fig, 2, movable block whose actuating elements include Fig. 4 illustrates the forming or closed posiappropriate levers and linkage means 3 pivoted tion of the third step. to the block 2 at 4:. When locked in abutting 35 Fig. 5 is an open view of Fig. 4. relation the aforesaid blocks land 2 provide the 6 is a Sectional View of a tube at the aforesaid angular cavity whose major leg forms line 6 f Fig 4. a cylindrical bore C wherein is slidably shift- 7 is the f th forming step able a spherically concaved piston 5 arranged to slide as an abutment which recedes under a pressure opposed by a resilient means 6, encompassing the pistons stem 7. The piston and stem means maybe cushioned as shown, or by any other suitable arrangement which may be i 10 an alternative Sealmg means regulated to emciently function as a resisting 45 11 1S perspectlve of the g tube stop that will give way under a certain pressure P Q and at a desirable speed necessary to accord Fig. 12 is the result obtained from the first with a product being worked or f d by the S P- assembly. The vertical leg 0" of the said'cavity I Fig. 13 is. t e e u Obtained in the Second is disposed to axially align with a fixed bore 8 50 step. wherein reciprocates a plunger P. The said Fi 14 Shows an pp mat V w f h figure discloses a condition obtaining at the product worked after the fourth step. end of an initial operation on the product or Fig. 15 shows the final result obtained in the tube T, Fig. 11, which has been angularly bent fifth step, with the ultimate aspect indicated by as seen in Figs 12. The next movement is to d tt d 11 1 raise the plunger P to clear the cavity portion Fig. 8 is the fifth and final forming step.

Fig. 9 is a detail of a fluid sealing means employed in the first and final steps, Fig. 1 and Fig. 2.

C" and the bore 8, withdraw the-block 2 towards the left, to where the formed product,

and piston occurs adjacentthe elbow t of the said cavity, where the piston, shown dotted, has been advanced to meet said tube. The tube or product T, in the present operation, is filled with a fluid ,f. to Within-a predetermined distance from its open end. It is then inserted in the bore 8 as shown dotted. The plungers reduced end P is supplied with an appropriate sealing disc S which compresses the said fluid to where a shoulder P" abuttingly meets a circular brim c of the tubes open end. With the fluid ,f compressed as a solid in the tube the said plunger descends to where the spherical end T enters the cavity of the piston 5 and from this meeting forward both piston and tube remain in their nested relationship until the product is formed as this step intends. The ductility of the metal tube T, the accuracy of the cavitys contours, the cushioned opposition of the said piston, and the flexible, while solid, characteristic of the fluid content, combine to produce an arcuately angular tube of uniform diameter and unchanged gauge thickness, which will be free from wrinkles, strains, or thinning stretches of the metallic body. This is possible by virtue of the receding behavior of the piston 5 which is in keeping with the tubes advance into the cavity C, thereby preventing any inordinate straining of said tube when undergoing the initial change just described. The sealing of the fluid may or may not be exactly as shown; either of the disclosed methods shown in Figs. 9 and 10 will produce equally satisfactory results whether the element S be a separate or an attached disc. Individual discs S maybe placed in a number of the ,tubes and these discs trued up to seal the fluid effectively upon entrance of the reduced end P. The forming result, as completed by the foregoing operation, is termed X, Fig. 12.

The bent tube X is next subjected to forming changes produced by the assembly, illustrated in Fig. 2. A suitable bed-block 10 and its divided die-block 1111' are arranged to form an angular cavity Ca wherein occurs a mandrel 12 which latter is held in a non-rotative and accurately centered relation within the.said cavity bywmeans of a flanged and hardened bushing 13 and a forked form of pivoting 14 where the mandrel is connected to a flat link element 15 and actuated by suitable means including a bell-crank lever 16 or' any other appropriate hook-up; The mandrel12 has a semi-spherical terminous or nose 12 which coincides with the elbow formation t of the previously bent tube T. The section 3--3, Fig; 3, shows the divided blocks 11-11 articulated, or

- hinged together at ha, and provided with a lockmeans in the form of a hook it which latter shoulders under the ledge 11b. This arrangement forms a'clamp which holds the cylindrical portion T of the tube where its brim -c will abut the flange 13 of the bushing 13, and resist tendencies to move when subjected to forces resulting from the pressures applied in tapering a portion of the tube T. The result of the flrst operation X is inverted in the cavity Ca to bring the brim 0 against said flange while the block 11 is swung open as arrow indicates in said Fig. 3, the blocks 11-11 are then latched, leaving the closed end of the tube T extended above the blocks. The said tube is inwardly clamped in the position shown by the'elbowpinching contact of the snugly fitting mandrel nose 12'. While held as described, the tubes closed end extending above the die-blocks is subjected to the tapering influences of separate but similar die-punches Pa whose conical bores Pa will offer a series of varying tapers which-compel the upstanding portion of the tube T to be elongated by a series of compression steps, as shown dotted, until the object X takes the form disclosed as Xa in Fig. 13. The tapering steps performed by the separate die-punches Pa will vary in number and degree of taper with the variable ductile characteristics residing in the particular product worked; here the steps are indicated as X1, X2 and X3. The just described operation, or second step, does not require a fluid medium. When completed the object Xa is easily re-' moved by raising the punch, unlatching the hook h, and withdrawing the mandrel 12, as lever arrow inFig. 2 indicates. Each punch, it will be noted, has a conically bored apron Pa" arranged to snugly fit about the perfect circle, or regular tube form at elbow t, thereby outwardly cooperating with the inwardly disposed mandrel nose 12.to prevent distortion of the hollow tubular elbow immediately under the punch.

Figs. 4 and 5 disclose a tapered tube bending arrangement by which the object Xa, just described, is given an ogee or reverse-curve aspect along the tapered neck X3. Die-blocks 1'7 and 17' are pivoted to rock about their respective pivots 18 and 18', fixed in a base 19. The said blocks are each provided with structurally integral gear segments 20 and 20 which intermesh to assure a positive and uniform angularity in said blocks when a plunger-like dieblocl: 21 descends upon the formed product Xe in order to affect the curvature noted. The blocks 17 and 17 and 21', when in forming relation, are grooved out as shown to provide a curved and tapering bore which is determined to have a purposeful contour that afiects the object Xa so that same willbe somewhat malformed intentionally along the arcuate taper portion X3 which this operation produces, in-

orderto get the desired sweep of the og'ee bend,

but still restrained by the said bores formation in order to prevent an inordinate crushing or flattening of the tubular spout beyond a metal fatiguing phase which might prevent the sinuously curved portionfrom being, later on, pressed back into an unimpaired but irregular circular cross-sectional aspect after said malforming has imparted a noticeable but helpful Fig. 6 shows the sectional aspect at the medial bent area of the objectxb, indicated by the line "6 of Fig. 4 where thetube has been excessively crushed X3 to get the longitudinal curvature desired. v

Fig. 7 shows the fourth step which is an operation requiring the application of simple forming die-blocks 23 and 24, movable as per arrows, which restore the elliptical aspect, X3, back to the circular form shown dotted in said figure. The operations of the third and fourth steps produce irregularities in the form of slight bulges and shallow waves in the metal handled which are eliminated in Fig. 8 ,which is the last forming operation.v The procedure here is similar to the initial step of Fig. l. Anaccurately formed and smoothly finished cavity Cd is produced by a slidable die-block 1 and a stationary block 2'. the object Xb is inserted as shown, flll in this instance with a fluid f. The tubular portion T projects beyond the blocks 1 and 2' when a ram-like plunger R envelops said portion simultaneously with the entrance of a plunger R having a sealing disc Sa that functions similarly to the like means P and P" of Fig. 1. The ram offers a shoulder R" which abuts the brim c and the pressure exerted compels the fluid f" to force the metal wall of the tube element to take the form of the aforesaid cavity, and eradicate all traces of the irregularities resulting from the third and fourthoperations, thereby producing the object seen in Fig. 15.

The commercial object will have a flange m,

and the closed end of the tube will thenbe cut' open, as at 11; these additional features are further operative steps produced by well-known methods which needno. recital here.

The several assemblies performing the foregoing steps may be grouped in closely related orders of sequence that will simplify and speed up production. The essentialconcern here is; the moderation of applied stresses to which the sheet-metal product is subjected, the equally moderate and progressive changes made, all allow said metal to flow easily into the shapes taken, which changes do not, at any stage, stretch or crowd the stock into lessening or thickening the original metal gauge, thereby minimizing seconds" or culls. This accomplishment pro-, duces an object of uniform strength throughout, and ofiers a smooth surfaced hollow article that requires a minimum of finishing and polishing treatment for arriving at the commerical essary in the sheet-metal, or equivalent, arts.

Having described the invention what is de-' sired to claim and protect by United States Letters Patent, is:

1. Forming means having, a sheet metal tube forming assembly embodying a reciprocative die-cavity-completing block abutting a fixed dieblock to form a piston bore, a piston element resiliently reciprocative in said bore for resisting distortion of a tubular object fashioned While the former block is withdrawn and an opposedly grooved plunger-die, a hell under an endwise pressure that is opposed by said piston, said piston functioning as atube 3. Forming means having, opposedly grooved and separable members forming a cylindrical bore, said bore receptive to an enterable fluid sealing plunger, a resiliently urged piston element opposing said plunger when spaced there-,

from by a fluid charged tubular product that fills the bore between said plunger and the aforesaid piston element.

4. Forming means having, a slidable and a fixed dieblock abutting each other to form an angular tube-accommodating cavity, plunger meanssubject to power thrusting shouldering against and sealing the open end of a fluid fllled tube in said cavity, and a spherically concaved piston element abuttingthe said tube in axial alignment throughout the said tubes tenure in said cavity. I f

5. Forming means having, an angular tube receiving cavity formed in divided die-blocks, said cavity contoured to accommodate an elbow formation on said angular tube, a mandrel filling the bore of said tube and terminated to provide an interiorly disposed gripping nose formation registering with the said elbow formation for resisting longitudinal shifting of the aforesaid tube.

7. Formingmeans having, conically tapered forming plungers reciprocatively aligned with a projecting tubular product, said product held by' a die-block and clamped atan elbow formation within said block, aremovable ram element looking said. tubular product within said block to oppose a downward pressure offered by said plungers, said plungers progressively encompassing said product in descending steps and compressing said tubular product to vary its conically changed aspect, said plungers effecting elongation of said product above the aforesaid die-block.

8. Forming means having, a singular dieplunger, pivoted die-block members geared together. to rock in unison forming an angular tube-shaping abutment, said blocks rockably responsive to pressure applied by said plunger to leave an object intermediate the plunger and die elements arcuately free across the abutting plane of said die-blocks.

9. Forming means having. a divided 'arcuate cavity formed of opposedly tiltable die-blocks dowel stud. element on. one of said block: positioning the elbow portion of a hollow tubular object tapered beyond said portion, said blocks divided medially of the tapered portions an articulated die-block, forming a portion ofsaid cavity, lockable as a clamp about a cylindrical tube element at the aforesaid abutment; a mandrel plunger within said cavity,'said mandrel preserving the cylindrical form of the tube element in opposition to the clamping pressure of said articulated die-block.

11. Forming means having, a .dividedidieq blockassembly offering a definite cavity, a liquid filled tubular element imperfectly corresponding to said cavity, a dual plunger respectively abutting a rim of said element and sealing the liquid in said element, said plunger functioning as a pressure ram for simultaneously forcing said element into the aforesaid cavity and compelling same to expand and assume the contour of the aforesaid definite cavity.

JOSEPH MIO'I'KEK 

